7000i is a 'style' speaker range where the focus is on getting the biggest sound from the smallest, best-looking speakers. This is done by moving as much of the bass as is possible into a subwoofer, enabling the designer to make much smaller speakers for the front and surround channels, each with their mounting method as part of the clever design.
Moving away from a fibreboard cabinet gives more flexibility for getting the best acoustic shape and appearance. Of great importance is that there is enough overlap between the speakers and subwoofers bandwidth to ensure that they crossover seamlessly without any gaps or peaks. This has been done by giving the 'satellite' speakers enough low-frequency extension that they can actually be used on their own.